Ball valve

ABSTRACT

A ball valve is provided for threaded connection to a separable component  72  having male threads  74 . A housing  10  contains a ball  12  selectively rotatable for passing fluid through the housing, and a flange member  20  threadably secured to the valve housing. A stop ring  16  is positioned outward of the valve housing and engages the flange member. A coupling  20  is threadably secured to the stop ring and includes female threads for engagement with male threads on the separable component.

RELATED APPLICATIONS

This application claims priority to U.S. application Ser. No. 12/348,977filed Jan. 6, 2009, which is hereby incorporated herein by reference.

FIELD OF THE INVENTION

The present invention relates generally to a fluid disconnect system foruse with a ball valve. More particularly, this invention relates to aball valve which may reduce the amount of trapped fluid that is ventedduring a disconnect operation. The invention also relates to a ballvalve with a minimum restriction to the flowing fluid and adaptabilityto an industry standard connection.

BACKGROUND OF THE INVENTION

Fluid connections in flow lines are commonly used in the transportationand distribution of products, such as propane and anhydrous ammonia.These fluids, when vented to atmosphere, are regarded as harmful to theenvironment. It is thus desirable to minimize the amount of liquid thatis trapped in a connection upon closure of the upstream and downstreamvalves. U.S. Pat. Nos. 6,237,633 and 6,155,295 discloses an improvedflow connect system that minimized the release of product during adisconnect operation. The system includes an inlet ball valve memberwith it's outlet port configured as an industry standard male acmeconnection and a downstream check valve with it's inlet port configuredas an industry standard female acme “hammer union” type connection.While this system provided for minimal flow restriction and minimalrelease of trapped liquid upon disconnect, it failed to address theindustry standard of a male acme connection at the inlet port of thedownstream valve.

With the configuration of '663 patent, the user would have to convert afleet of vehicles using the patented system because once the upstreamvalve was converted to the male acme configuration, it would no longerconnect to the normally configured male acme connection in the vehiclefleet. Other patents disclosing ball valve disconnect systems includeU.S. Pat. Nos. 4,023,773, 4,124,036, 5,255,121 and 6,056,012.

In various applications, it is thus desirable to use a ball valve forthe upstream valve for flow considerations, but to have its outlet portconfigured with a female acme connection. In this situation, the fillingstation could still connect to and fill a truck outfitted with theindustry standard male acme connection, although the released product atdisconnect would be greater than if the vehicle were outfitted with acheck valve that minimized the product release. With this setup, thefleet of transport vehicles can be converted gradually to reducedrelease downstream check valves while allowing the filling operation toconnect to all the vehicles in the fleet.

The disadvantages of the prior art are overcome by the presentinvention, and an improved ball valve for threaded interconnection to aseparable component having a male thread is hereinafter disclosed.

SUMMARY OF THE INVENTION

A ball valve is adapted at its outlet port with a flange member thatprovides the downstream ball seal functionality and provides a thrustsurface for a two piece female coupling, such as a hammer union. In oneembodiment, prior to fixing the flange member in place, a stop ring ispositioned over the downstream end of the ball valve, such that it willbe upstream of the flange member once connected. A locking membersecures the ball valve housing or body and the flange member, and apressure seal between the main body and the flange member isolate theball valve internal pressure. An internally threaded coupling, such as afemale acme hammer union, may then be connected to the adapter ring andlocked in place. In another embodiment, the flange member is axiallysecured to the ball valve housing by ball locking members.

The present invention allows for a standard two piece ball valve with afemale acme outlet connection, such that the distance from the acmethreads of the connection to the surface of the ball on the closed ballvalve is minimized for the purpose of minimizing the release of trappedfluid at disconnect.

These and further features and advantages of the present invention willbecome apparent from the following detailed description, whereinreference is made to the figures in the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a cross-sectional view of the female acme adapted ball valveconnected to a downstream check valve for minimizing the total releaseof fluid at disconnect.

FIG. 2 is a cross-sectional view of a standard ball valve and downstreamcheck valve outfitted with industry standard female and male acmeadapters.

FIG. 3 is a cross-sectional view of another embodiment of the inventionwith the coupling bolted to the stop ring.

FIG. 4 is another embodiment of the invention wherein the coupling isthreaded and pinned to the stop ring.

FIG. 5 is yet another embodiment of the invention, wherein locking ballsaxially interconnect the stop ring and the coupling.

FIG. 6 is another embodiment of the invention, wherein locking ballsaxially interconnect the coupling and the ball valve housing.

FIG. 7 illustrates another embodiment of the invention, wherein theflange member and the coupling are axially connected.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

FIG. 1 illustrates a ball valve assembly comprising a ball valve body orhousing 10, a ball 12 and ball seals 14. The handle, stem and stem sealsystem are not shown, and may be of the type standard to the industry. Asuitable handle and stem are shown in FIG. 2. Threaded stop ring 16 isplaced over the body outlet end 18 and then flange member 20 is threadedto body 10 at thread 22, forming a pressure seal with o-ring 24. Stopring 16 is slipped toward valve body stem hub 26 to provide clearancefor making up a connection using pin member 28. Locking pin 28 locksbody 10 to flange member 20 and provides a pressure seal with body 10 atthreads 30, so that pin 28 clears the inner diameter of threaded stopring 16.

Female acme union 32 is then threadedly connected to stop ring 16 atthread 34 and locked in place with one or more locking pins 36. Thisarrangement provides for a minimal distance 42 between the face 43 ofclosed ball valve 12 and the seal face 38 on the flange member 20,defining a volume 40 therebetween, which preferably is between 0.9 and1.6 cubic inches on a system using a 2 inch ball valve and a 3¼ inchacme which is the most common combination.

FIG. 1 further shows a downstream check valve 72 adapted with a maleacme 45 and a poppet member 44 which has a nose 46 formed on an end ofthe poppet member to occupy most of volume 40 when the ball valve isclosed, therefore providing a minimal release of product at disconnect.

FIG. 2 shows a prior art upstream ball valve 48 and a standarddownstream check valve 49 outfitted with industry standard female andmale acme adapters to facilitate connection. This arrangement wouldallow the release of from 18.0 to 22.0 cubic inches of product atdisconnect, since the released fluid occupied the entire volume from theface 52 of the closed ball 54 to the check valve seal 55. The male acmeadaptor 56 threaded to the check valve 49 could be designed to reducethis volume. The ball valve and female acme connection may be revised toshorten member 62 and thereby reduce volume 64 between the face 52 ofthe closed ball valve and seal face 65 of the acme adapter. The presentinvention provides for a much greater reduction in volume 64 than wouldbe possible by simply shortening member 62.

The method of assembling the ball valve as shown in claim 1 issignificant to the present invention. The first operation involvesplacing the stop ring 16 over the outlet of housing 18, and pushing thestop ring toward the valve stem so that the flange member 20 may bethreaded to the valve body, then the threaded pin inserted to connectthe valve body and the flange member. Stop ring 16 may then bepositioned against the retaining surface 21 on a flange member 20, andthe coupling 32 then threaded to the stop ring 16 and pin 36 inserted tofixedly connect the stop ring and the coupling. Seals 14 held in placeby the flange member maintain reliable sealing engagement with the ball12. A suitable separable component, such as check valve 72 with malethreads 74, may then be threaded to the coupling 32, with seal 76providing a fluid tight connection between the flange member and thebody 78 of the check valve. The check valve includes a stem end member80 which occupies most of the volume 40 when the check valve is closed,with that member being biased toward the closed position by coil spring82. Other suitable components may be provided separate from a checkvalve, although the check valve as disclosed herein satisfies the desireto minimize the volume of released material when the connection isbroken.

Although the flange member 20 may have various configurations, a stopsurface projecting outward from the valve body is provided forengagement with the stop ring. The flange member is preferably ringshaped to maintain strong structural integrity of the connection, andthe stop ring 16 is also preferably ring shaped. Further detailsregarding a suitable check valve are disclosed in U.S. Pat. No.6,155,295.

As discussed above, flange member 20 supports seal 14 for sealing withthe ball, and a separate seal 76 is provided for sealing between theflange member and the separable component 72. Flange member 20 also hasa circular interior diameter for closely receiving the stem head of aseparable component which may rest in close proximity to the face of theball when the stem head is in the closed position.

In FIG. 3 embodiment, a modified flange member 20 is used, and the unionor coupling 32 is secured to stop ring 16 with multiple bolts 80 eachhaving an axis 33 substantially parallel to the central axis 19 of thehousing 18. Since the union is typically tightened by striking it with asmall hammer, and since the valve may be used for propane service, theunion is preferably made of non-sparking material, such as brass. Thisdesign has a larger female union than the FIG. 1 embodiment whichincreases the weight and therefore the cost of the union. Moreover, thestrength of the connection is a function of the strength of theattachment bolts 80, which are necessarily small relative to otherthreads in the connection.

FIG. 4 illustrates another embodiment, wherein the union member 32 isconnected to the modified stop ring 16 by threads 34. In this case,threads 34 are as strong as the other threads in the connection. Lockpin 82 may be installed to lock the stop ring 16 to the coupling 32, andthe coupling is only slightly larger than the FIG. 1 embodiment. Lockpin 82 may be installed either radially through thread 34 (perpendicularto axis 19) or parallel with the axis 19 as shown in FIG. 4 with pin 84.

FIG. 5 is yet another embodiment in which the stop ring 16 is placed onbody or housing 10, then the flange member 20 threaded to body 18 andlocked in place with a threaded lock member 28. Stop ring 16 andcoupling 32 both have one-half of a ball race with a circularcross-section machined therein. Coupling 32 and stop ring 16 are placedso that the ball races are aligned, so that multiple ball lock members88 may be fed into the race through threaded port 90 and then retainedwith threaded plug 92. Stop ring 16 is retained by flange 20, and theunion 32 is free to swivel about the axis of the ball valve. The ballmembers axially connect the stop ring and the coupling, such thattightening the coupling on a male threaded component forces the stopring into secured engagement with the flange member. Wear between theflange member 20 and the stop ring 16 during rotation of coupling 32 issubstantially eliminated by the presence of the ball members 88, whichprovide a substantially frictionless thrust surface as the union 32 istightened to the male member. This embodiment is lightweight and robust,and the locking balls provide significantly reduced wear and lowoperational friction. In the event that debris prevents the ball members88 from circulating in the ball race, the unit will still function untilthe ball race is cleaned because the stop member 16 will simply slideand thrust against flange member 20.

In the FIG. 6 embodiment, locking ball members directly engage the valvebody 10, being positioned in a race in the valve body and in thecoupling 32. Ball locking members 88 may be fed through a port in thecoupling and maintained in place by a threaded plug 94. The coupling maybe assembled close to the ball face since the flange portion 96 whichengages an end surface on the valve body may have a minimal thickness.This proposal avoids the use of a stop ring, since the coupling isrotationally locked to the valve body by the locking balls. In the eventof debris preventing circulation of ball locking members 88 the unitwill be rendered inoperable until it is cleaned therefore this is a lessthan optimal solution. The cross section of the valve body between itsflange engaging threads 98 and the deep portion of the ball race in thevalve body is relatively thin, which weakens the connection. To overcomethis problem, the thickness of at least the downstream end of the valvebody outlet end adjacent the threads 98 may be increased to compensatefor the reduction in thickness due to the ball race in the externalsurface of the valve body.

FIG. 7 depicts yet another embodiment of the invention wherein aradially outward portion of flange 20 is secured to the coupling 32 by aplurality of locking balls 88 fed through a port in the flange and heldin place by the threaded pin member 94. Flange member 20 is preferablythreaded to the valve body at threads 98, and is rotationally secured tothe valve body by pin 28.

This embodiment has the advantage of eliminating the stop ring of FIG. 5which would reduce cost. However, as in both the FIGS. 6 and 7embodiments, if debris jams up the ball race, then the assembly iseffectively out of commission until the race is clean.

Although specific embodiments of the invention have been describedherein in some detail, this has been done solely for the purposes ofexplaining the various aspects of the invention, and is not intended tolimit the scope of the invention as defined in the claims which follow.Those skilled in the art will understand that the embodiment shown anddescribed is exemplary, and various other substitutions, alterations andmodifications, including but not limited to those design alternativesspecifically discussed herein, may be made in the practice of theinvention without departing from its scope.

What is claimed is:
 1. A ball valve for threaded connection to a checkvalve having a male thread and a stem head configured for mating with asurface of a ball of the ball valve when the check valve is closed,comprising: a ball valve housing containing the ball rotatable by a stempassing through the ball valve housing; a flange member removablysecured to the ball valve housing and supporting a seal for sealing withthe ball; a stop ring positioned outward of the ball valve housing andengageable with a stop surface on the flange member; a coupling axiallyremovably secured to the ball valve housing, the coupling beingrotatable with respect to the ball valve housing, the coupling includingfemale threads for engagement with the male threads on the check valve;and the stop ring and the coupling being axially connected against axialseparation by a plurality of ball locking members positioned within arace in the stop ring and the coupling, the plurality of ball lockingmembers being removable from the race independently of removal of thecoupling from the ball valve housing, whereby the coupling can beremoved from the flange member where the flange member is still securedto the ball valve housing.
 2. A ball valve as defined in claim 1,wherein the stop ring can rotate with respect to the ball valve housing.3. A ball valve as defined in claim 1, wherein the coupling is axiallycoextensive with at least a portion of the ball.
 4. A ball valve asdefined in claim 1, including a seal for sealing the flange member tothe check valve when connected together.